The Progeny Refutation of the Chronology Protectio
by Alyce Gates
Summary: Penny finds a lost toddler outside her apartment one evening and goes to Leonard for help, but only Sheldon knows what's really going on... Penny/Sheldon
1. Chapter 1

Title: The Progeny Refutation of the Chronology Protection Conjecture

Author: Alyce Gates

Rating K

Summary: A Big Bang Theory Time Travel Fic (Penny/Sheldon)

Note: This is my first BBT fic, so be nice.

I have a whole series planned for this fic if it's well received. There will be a prologue, three parts, and an epilogue for this story.

Special Thanks to Syrus, my awesome beta.

Prologue

Two quietly bickering twelve year old boys hurried down the sidewalk passing a comic book back and forth between the two of them. They looked almost identical with the same short, dark brown hair, piercing green eyes, and tall thin frames, but that is where the similarities ended. One was half an inch shorter with a slightly bigger, more muscular build. He wore stylish jeans and a black hoodie over a faded band t-shirt. The other had a pair of round glasses perched on his nose and wore khakis and a slightly too large brown leather jacket over a bright red t-shirt with an equation printed in yellow on the front.

"Zach, I can't believe you took such a huge risk for a stupid comic book," the shorter one hissed staring at the cover in disgust.

"It is not stupid, Benjamin! This happens to be an original, mint conditioned Flash 123, Classic Flash of Two Worlds," Zach, the one with glasses, retorted.

"Whatever! If Dad finds out that we used the machine for this…"

"Our father will be delighted once he sees what I have used his invention to procure. He has long lamented the loss of this particular comic book to Uncle Howard in an ill-conceived cricket wager years ago," Zach insisted carefully removing the comic from Ben's hands and slipping it inside a protective wrap.

"I still don't understand why you had to go back in time to get it though. Why didn't you just get it from Uncle Howard in the present time? And why are you getting him anything anyway? Dad has made it very clear that he doesn't like gifts," Ben pointed out.

Zach rolled his eyes at his younger by six minutes brother's lack of intelligence.

"Firstly, Uncle Howard sold this comic, along with several others, years ago so he would have enough money to buy Aunt Bernadette's engagement ring. I had to come back to this moment, a few weeks after the sale, to buy it back from the store. I traced the sales and found my name as the buyer on this day and time so I had to go through with it or risk creating a paradox. Simply put, I had to do it, because I had already done it."

Ben rubbed a hand over his face and shook his head.

"Talking to you makes my head hurt," he said, but Zach continued on.

"And the reason our father does not appreciate gifts is because he views them as obligations. I want him to feel obligated to bring me along when he, Uncle Leonard, Uncle Howard, and Uncle Raj go to DragonCon next month," he concluded with a triumphant smile.

"But Mom's taking us to Disney World then, remember?" Ben reminded him.

Zach stopped walking and gave his brother a sharp look.

"Disney World? Honestly Benjamin, sometimes it's hard to believe we share DNA much less a womb for 9 months.

"Well, Dad might be okay with this, but Mom is going to freak! Especially if she finds out that we brought Lizzie," Ben pointed out and started gestured for Zach to hurry.

Zach glared as rushed to catch up.

"If you recall, I didn't want to bring her along, but you insisted..."

"Mom told us to watch her! We couldn't leave her alone at home. If I'd known you were just going to get a comic book I'd have stayed there with her," Ben groused.

They continued walking in silence for a minute.

"Do you think she's okay?" Ben asked.

Zach rolled his eyes and consulted his watch, "Of course she's okay. She was out cold, and we've only been gone 6 minutes and 22 seconds."

He didn't feel as sure as he sounded.

The boys rounded a corner and stopped abruptly. They blinked in shock at the empty cart that had held their sleeping sister only minutes earlier.

* * *

Penny climbed out of her car and sighed in relief. Saturdays at the Cheesecake Factory were always the worst. Messy kids, birthdays, half the kitchen staff walking out after getting paid the night before…

It was over now though, and she had a nice wad of tip money in her pocket and a chilled bottle of wine in her refrigerator. As she walked toward the apartment building she scratched off some dried mashed potatoes from her uniform and smiled. Saturday meant laundry night. One of her least favorite chores that was always more fun when she could mess with Sheldon.

She smiled when she thought of her crazy neighbor. Penny would never admit it, but since she and Leonard had decided they worked better as friends she had grown much closer to Dr. Sheldon Cooper than she thought possible. The theoretical physicist had been spending a lot of time with her lately. They ate a meal together by themselves at least once a week, went shopping, and most recently, had started doing their laundry together.

Sheldon had confided in her just that past week that he felt his other friends were moving on from him. Leonard was dating a very unsavory new girl that had a habit of blowing her nose in front of everyone while they were eating. Things were getting pretty serious between Howard and Bernadette resulting in the short Jewish man cutting back on the amount of time he spent with his friends. Even Raj wasn't over as often due to the sign language classes he took three nights a week to help him communicate with his new deaf girlfriend.

Sheldon had gone on to ramble some long diatribe of slight insults that added up to a backhanded revelation that he now considered Penny his best friend. As usual Penny was unsure if she wanted to hit him or hug him, but had settled on a polite smile and answered that she considered him a very dear friend as well.

Of course he had then ruined the moment by pointing out the odds that someone of his IQ could possibly maintain any kind of feasible relationship with someone of her IQ. Then the insults had started flying between the two of them, as was their normal routine. Sharp, and made to hurt. But the longer they verbally sparred, the more ridiculous they both felt and, more often than not, it would end with Penny dissolving into giggles while Sheldon smirked at her, blue eyes sparkling with suppressed mirth.

A young voice screeching, "Mommy!" broke her from her thoughts of Sheldon, and made her freeze with her hand on door knob to her building.

There was something so eerily familiar about that voice, that it sent shivers down her spine.

Penny felt her mouth drop open in shock at the small form stumbling toward her. Big watery blue eyes looked at her pleadingly through tangled blonde hair.

"Mommy, Mommy, Mommy," the toddler chanted.

Penny looked around anxiously, but the street and sidewalk were deserted.

The little girl threw her arms around Penny's legs and sobbed into her skirt.

"Aww, it's okay, Sweetie," Penny cooed and swung the girl up into her arms as if it was the most natural thing in the world.

"See, everything is just fine," she murmured as the little one buried her face in the collar of Penny's shirt.

Penny wasn't sure what to do. She walked down the street a little ways and turned a corner catching the eyes of a few passersby. Eyes slipped over the young girl with no recognition. She asked a few people, but none had seen the child before. She walked back to her apartment building, but still didn't see anyone. The sun was starting to go down. She couldn't just keep standing there all night. Where were the girl's parents?

She gave one last look around before she stepped into the apartment lobby and took a seat on a small bench next to the mail boxes.

Penny pulled a folded napkin from her pocket and wiped at the tear tracks on the toddler's face. Again she was struck by an odd sense of familiarity concerning the little girl, but Penny couldn't place her.

"Hi there," she said, giving the toddler a big cheery smile.

The girl smiled back and giggled then threw her arms around Penny's neck.

Penny giggled herself when the toddler planted a sloppy wet kiss on her check.

"Mommy," the toddler sighed happily.

Penny blinked in confusion and looked around the empty lobby.

"Do you mean me? No, I'm not your Mommy. I'm Penny. Can you say 'Penny'?" She asked.

The girl tilted her head and arched an eyebrow at Penny like she thought the waitress was insane. It was shocking to see that expression on such a young face, but strangely familiar.

"Ok, what is your name then?" Penny stammered a little unnerved.

"Lizzie," the girl said, and started playing with the buttons on Penny's jacket.

"Well, Lizzie, we can't just sit here all night. Let's go to my place and I'll get you cleaned up. Then I can figure out what to do.…" Penny trailed off as she got up from the bench and turned toward the stairs.

She froze with her foot on the first step when she felt someone watching her. Turning her head quickly, she peered out the glass door of the building but didn't see anyone. She needed to talk to Leonard. He would know what to do.

* * *

The twin boys watched in dismay as Penny carried their little sister up the stairs and out of sight.

"Astounding! The odds that of all the people walking these streets this evening, the one to find Lizzie would be…"

"What do we do? Our mom is going to kill us!" Ben cried.

"Calm yourself," Zach commanded narrowing his eyes at the now empty stair case.

"Father will know what to do."

End Prologue

Let me know what you think! Chapter 1 will be up in the morning.

-Alyce


	2. Chapter 2

Title: The Progeny Refutation of the Chronology Protection Conjecture 2/5

Author: Alyce Gates

Rating K

Summary: A Big Bang Theory Time Travel Fic (Penny/Sheldon)

Special Thanks to Syrus, my awesome beta.

Note: I found time to format chapter one tonight! Enjoy...

Chapter One

Leonard walked Carole, his new girlfriend, to the door of his apartment, apologizing once again for his roommate's rude behavior.

"Dr. Cooper doesn't bother me, Leonard. You are worth it," She confessed with a small smile.

Leonard felt a pleasant warmth spread through his chest and leaned forward to kiss her.

Carole Williams was pretty, sweet, and though she did not have a doctorate, as a high school chemistry teacher, she was able to hold her own in some of the more complex discussions the two of them had about Leonard's work. She was everything he could ask for in girlfriend, even if she had a couple of annoying habits. Being with Carole made Leonard happier than he had any right to expect. There was only one problem. She wasn't Penny.

As if his thoughts conjured her, the door to 4B opened and he met the troubled green gaze of his friend and neighbor. Even though Penny immediately shut the door again to allow them some privacy, Leonard put a quick end to the kiss.

"Good night, Leonard. I'll see you in the morning," Carole said patting his cheek fondly.

Leonard watched her go, and turned to look at Penny's door. She opened it and stepped into the hall.

"So, things seem to be going well with Carole," she commented, awkwardly.

"Uh, yeah. Things are going surprisingly well, actually," he admitted, smiling.

"Though, Sheldon still doesn't like her…" he trailed off with a pained look.

"He didn't like me in the beginning either," she pointed out.

"Yeah, but at least he hung around you and made an effort. When Carole comes over he hides in his room… Hmm, maybe that's why things are actually working out for me with Carole," Leonard quipped.

Penny treated him to her soft laugh that always melted his heart. And he had to physically shake his head to keep from falling under her unintentional spell. He and Penny were not meant to be, hard as that was to accept, he had to. He had moved on. To Carole…

"Are you okay? You looked a little worried earlier," he asked.

Penny glanced back at the closed door of her own apartment.

"Can we not talk in the hall? I could really use your advice on a situation that has come up."

"Sure thing," he said, opening the door to his apartment and gesturing for her to precede him inside.

"Thanks, Leonard. I just really have to talk to someone right now."

"Anything you need," Leonard responded.

"Penny, where is your laundry? It's almost 8:15pm you know," Sheldon said emerging from his room with a full basket.

"Hi Sheldon, it's nice to see you too," she said, with exaggerated sweetness.

He simply stared at her expectantly.

"Sheldon, Penny needs to talk to me. Why don't you go on down, I'm sure she'll catch up with you later," Leonard said, shooing him toward the door.

Sheldon looked at Penny, whose expression had turned troubled again. He looked back and forth between his watch, the laundry basket and the door a few times. He glanced at Penny and Leonard once more, then determinedly strode to the door.

Penny sniffed and Sheldon froze. A muscle twitched in his cheek then his whole body slumped and, with a 'put-upon' sigh, he placed the basket on the floor then turned to face them expectantly.

"Alright Penny, let us hear what new predicament you've gotten yourself into now. And it had better be catastrophic, as it is interfering with laundry night. Just know, if the solution involves facing your ex-boyfriend Kurt again, I will not be a part of it," he said taking a few steps toward them.

"Sheldon, Penny wants to talk to **me**. You go ahead and do your laundry," Leonard said with clenched teeth.

Sheldon shook his head.

"I can't."

"Why not?"

Sheldon took a breath.

"Given our past experience with the kinds of _situations_ that Penny finds herself involved in, it would be in her best interest for me to remain and offer my advice which is sure to be vastly superior to your own." Sheldon said a matter of factly, emphasizing the word 'situation' with air quotes.

Penny's lips twitched, but she remained silent.

"What? Since when do you care about anyone's interests other than your own?" Leonard asked, genuinely confused.

"The insertion of Penny into my daily, weekly, and even monthly routines has created a new paradigm that requires her compliance and cooperation to maintain the balance that is essential to my best interests. This new situation is disrupting her routine, such as it is, and disrupting my own. I don't like being disrupted, Leonard."

Leonard turned to Penny with his head tilted and eyes squinting.

"I think that's his way of saying he wants to help you because you are his friend."

They both looked at Sheldon, who fidgeted uncomfortably.

"Is that not what I said?" He asked, quietly.

Penny smiled, eyes shinning brightly, "I love you too, Sheldon."

He gave her a sharp look, but Leonard motioned for them to sit. He and Sheldon sat on the couch, while Penny took the chair.

"Okay, Penny, you have the floor," Leonard told her.

"Ridiculous expression. How can one 'have the floor'? Absurd," Sheldon grumbled, but was ignored.

"Well, I found a little girl outside our building when I got home from work earlier. She was all alone, and crying so I took her to my apartment…"

"You kidnapped a child? Penny, how could you?" Sheldon tsked, shaking his head.

"I didn't kidnap her, Sheldon! I tried to find her parents, but no one knew who she was. What else was I supposed to do, leave here there?" She demanded.

Leonard stifled a sigh, tired of always playing the peacemaker between the two of them. Sometimes it seemed to him that they both just looked for reasons to get into an argument.

"Sheldon, calm down," he said.

"Calm down? How can I remain calm knowing that we are harboring a criminal in our home?" Sheldon demanded getting to his feet.

Penny jumped to her feet and stalked toward him, glaring.

"Criminal? I'm not a criminal! I called the police and filed a report over the phone, but they were so busy they asked me to keep her until someone could be sent to pick her up tomorrow," she shouted poking a finger into his chest.

Sheldon blinked and pursed his lips.

"Oh, well why didn't you say that to begin with?"

Penny sighed and shook her head tiredly.

Leonard cleared his throat.

"Well, that was nice of you to take her in, but I'm not sure what kind of advice we can offer…" Leonard began.

"Mommy!"

A shriek sounded from across the hall.

Penny and Leonard shared a glance then rushed over to Penny's apartment.

"You make her call you, 'Mommy'?" Sheldon inquired in surprise as he followed at a much slower pace.

When Leonard reached Penny's bedroom, he saw the small blond toddler in Penny's arms, her face buried in the waitress's shirt. The toddler was tied loosely into one of Penny's t-shirts and, the neck hole fell down over the child's left shoulder to reveal a small geometrical birthmark on the back of her upper left arm. Leonard heard Sheldon gasp behind him, but when he looked back, his roommate was nowhere to be seen.

"Don't leave me, Mommy," the toddler whimpered, capturing Leonard's attention once again.

Penny looked up at Leonard over Lizzie's head, eyes bright with tears.

"I don't know why she calls me that. I didn't tell her to," she insisted.

Lizzie's blue eyes caught sight of the physicist and she smiled.

"Uncle Leonard," she said succinctly as she held her arms out to him.

Penny looked up at him, stunned.

Leonard felt his stomach drop. Something was really wrong here.

"P-penny? Did you tell her my name?" He asked, shakily.

Wordlessly, Penny shook her head.

* * *

Leonard left the bedroom so Penny could try to get the girl to go back to sleep. He saw Sheldon pacing in front of Penny's door.

"Sheldon? What's wrong with you?"

The tall man was muttering under his breath as he paced, and his normally pale complexion was so white, Leonard was afraid he was going to pass out.

"It doesn't add up, Leonard. I don't have all the data. It's not my fault…" he trailed off continuing to pace.

Penny slipped out of her bedroom and quietly closed the door.

"What's with him?" She asked Leonard quietly.

Leonard just shook his head.

"Sheldon?" Penny asked, slowly approaching him.

He didn't acknowledge her, just kept pacing and muttering under his breath.

She sent a worried look to Leonard, then reached out a hand to grab Sheldon's arm. The tall man snatched her by the wrist before she could touch him. His eyes were intense when he looked at her.

"Penny, I need my marker board," he said, then dropped her wrist and left abruptly.

* * *

A couple of hours later, Leonard and Penny were sitting on her sofa a now empty bottle of wine between them.

"I just don't understand it, Leonard. It doesn't make sense," Penny said, not for the first time.

Leonard squirmed a bit as he said, "Penny, she looks just like you! I mean, she could be your daughter…"

He trailed off at Penny's glare.

"I would know if I had a daughter!"

He held up his hands in a placating gesture.

"Sorry, just trying to think it through."

Penny shrugged and slumped back against the cushions.

"You are right. She does look a lot like me. Like my mother even more… But her eyes, and her mouth. They bother me. I mean, I feel like I've seen them before, but I just can't remember," she broke off with a yawn.

Leonard stood and offered her a hand up.

"Get some rest. We'll talk it over again in the morning," he said, pulling her to her feet.

Penny smiled.

"Thanks Leonard, you're always so good to me," she whispered pulling him into a hug.

Leonard blushed, but was dismayed to realize that this was a 'friend' hug. The few months he had dated Penny allowed him to easily recognize the difference.

"You know where I am if you need me," he said, and left.

* * *

When Leonard returned home he found Sheldon scribbling what looked like random numbers and symbols on to his maker board and Leonard's.

"Sheldon! You erased my equations! I needed those," he yelled.

"Check your phone," Sheldon said, quietly as he continued to write.

Leonard pulled his cell out of his pocket and found that Sheldon had snapped a picture of his maker board before he had erased it and sent it to him.

"Oh. Thanks," he said.

But Sheldon didn't acknowledge him. In fact, Sheldon ignored him for the rest of the night. At midnight, Leonard gave up and went to bed.

It was nearly 7am when Leonard emerged the next morning to find Sheldon on the floor arms wrapped around his knees. He was rocking back and forth, gaze shifting from one marker board to the other. Both boards were packed with cramped writing that made Leonard's head hurt just to look at.

"Sheldon? You okay Buddy?" He asked gently.

Sheldon froze, then looked up at Leonard like he'd been caught doing something wrong.

Leonard raised his eyebrows.

Sheldon jumped to his feet and hurriedly erased both of the boards.

"I'm fine, Leonard. No need to be concerned. Give me a minute to get dressed and we can go to work," Sheldon said turning toward the bathroom.

"Uh, Sheldon? Today is Sunday."

Sheldon flinched and looked back at him with narrowed eyes.

"Right. I think I'll sleep now," he said, and padded off to his room.

End Chapter 1


	3. Chapter 3

Title: The Progeny Refutation of the Chronology Protection Conjecture 3/5

Author: Alyce Gates

Rating K

Summary: A Big Bang Theory Time Travel Fic (Penny/Sheldon)

Special Thanks to Syrus, my awesome beta.

Note: Thanks for the reviews! Keep 'em coming. ;-)

*Itallics means dream

Chapter Two

_Penny was running through the city. She rushed past pedestrians, cars, and bicyclers, miraculously not running into any of them. She was running as fast as she could, trying desperately to keep sight of Lizzie's blond hair. She only glimpsed it here and there as the toddler weaved in and out of the crowded sidewalk. As time passed Penny became more and more frantic. Suddenly, Sheldon appeared in front of her and grabbed her wrist. _

"_No Penny. It's time yet. You have to wait," he told her, in his annoyingly superior tone._

_She pulled and tugged, but could not break his hold._

"_Let go, Sheldon!" She yelled, but his grip just seemed to tighten._

_She looked frantically in the direction she had last seen Lizzie but the toddler was gone._

_The loss she felt was immense. It felt as if there were a huge gaping whole deep inside her. It took her breath away. _

_She crumpled to the ground, shaking with sobs. Sheldon's grip grew even tighter. _

"_Ow! Sheldon, let go! You're hurting me," she looked up at him through a veil of tears and saw him looking at her with the oddest expression. _

"_I don't want to hurt you, Penny," he said, gripping her wrist even tighter._

_

* * *

_

Penny's eyes flew open and she groaned at the stabbing pain in her wrist. She had been laying on it for what felt like hours. Sitting up in the bed she shook it, trying to get the circulation going and glanced at the clock. 9:15am.

Her nose picked up the smell of waffles and coffee and her stomach growled. The disturbing dream was already fading from her mind. She climbed out of bed and looked for her robe that she last remembered seeing on her bedroom floor, but it wasn't there. In fact, there was nothing on the floor. Her entire room was spotless and her robe was hanging neatly on the back of her closed bedroom door.

Well, that answered the question of who was making waffles in her kitchen. She tried to feel angry about the fact that Sheldon had used the emergency key to once again break into her apartment and clean, but couldn't muster the energy. She was more surprised that she'd slept through it all than anything else.

Penny stretched and went to put on her robe when she heard a sound that made her pause. It sounded like singing. Was Sheldon watching TV?

She pulled the door open, squinting through the bright morning sun streaming through her window. Her jaw dropped open at the scene in front of her. Sheldon was standing in the kitchen singing into a wooden spoon while Lizzie was sitting in a chair at the little table against the window. A couple of thick science texts were serving as a booster seat.

Sheldon was singing _Pirates of __Penzance_…

"…I'm very good at integral and differential calculus;  
I know the scientific names of beings animalculous:  
In short, in matters vegetable, animal, and mineral,  
I am the very model of a modern Major-General…"

Penny had heard Sheldon sing several times before, so that wasn't so shocking. No, it was Lizzie, who couldn't be more than two years old, 'singing' along that startled her. Lizzie wasn't singing the actual words, just singing the notes in a perfect pitch along with him.

"Penny!" Sheldon gasped when he noticed her.

"Uh…" Penny wasn't sure what to say, and was distracted by the way Sheldon was looking at her.

His eyes were wide, and his gaze traveled up and down her body. Very un-Sheldon like.

"Mommy!" Lizzie called happily.

Sheldon's head turned at the toddler's voice. He gave Lizzie a stern look and put his hands on his hips. The toddler put a small hand her to mouth and looked up a Sheldon with a guilty expression.

"Penny," she said, looking at Sheldon for approval.

The physicist just shook his head and turned to pull a coffee cup out of a cabinet.

Lizzie turned her head to Penny as soon as Sheldon looked away and gave her a wink.

"Good morning, Penny. Would you like some coffee?" Sheldon offered, pouring her a cup.

"Uh, yes?" Penny said, shuffling toward him.

Sheldon turned to hand the cup to her but froze when he looked at her again. He quickly looked away and held a hand over his eyes.

"Penny, do you know what the physical property of allowing the transmission of light through a material is called?"

"What?"

He looked at her again, being careful to keep his gaze on her face.

"Transparency."

Penny blinked then quickly looked down at herself. The white tank and boy shorts she had slept in the night before left little to the imagination while she was standing in the bright morning sunlight.

"Transper…cy!" Lizzie echoed happily, clapping her hands.

Penny gasped and quickly slipped on the bathrobe she had been holding in her hand.

"Sorry, Sheldon. I guess I'm not quite awake yet," she explained, flushing.

He held the coffee cup out to her again and she took it.

"Thanks."

"Your welcome. Have a seat," he gestured to the chair across from Lizzie.

Penny sat and sipped at her coffee while Sheldon served her and Lizzie waffles.

"Sorry I interrupted your concert," Penny said watching him cut Lizzie's waffle into tiny pieces.

"Just passing the time," he said as he worked.

She nodded and took another drink.

"So, Lizzie, is she… you know… like you?" Penny asked, hesitantly.

Sheldon's shoulders stiffened and he gave Penny a 'deer in the headlights' look.

"I mean, is she like, really smart or something?" She clarified, wondering why he looked so worried.

The physicist relaxed and gave her a nervous chuckle.

"She's too young to be officially tested, but clearly she demonstrates abilities well beyond her age. Whether her IQ is anywhere near mine remains to be seen. But in my professional opinion I'd say that yes, 'she is really smart or something'."

"Oh, well that's interesting. I probably should call the police station again. Surely her parents will be missing her by now," Penny said about to stand.

"Unessecary. I already spoke to them this morning," Sheldon said bringing a bottle of syrup to the table.

"Oh? What did they say? Is someone going to come pick her up?"

Sheldon focused very intently on the task of pouring syrup onto Lizzie waffle as he answered, "Tomorrow. It's Sunday, and they are shorthanded. Apparently the officer who would normally be assigned this case has contracted a case of mononucleosis and must not have contact with anyone for 72 hours."

Penny was surprised by the relief that flooded through her. One night with the little girl was not enough. She couldn't explain it, but there was a part of her that couldn't fathom letting the girl go.

It made it very easy to ignore the tell-tale tic in Sheldon's jaw that told her he was lying. Not to mention the weak excuse.

She laughed and stood up from the table.

"Sit down here, Sheldon, I'll share with Lizzie," Penny said, picking the girl up with one arm and removing the text books from the chair with another.

She sat down with Lizzie in her arms and giggled along with her as the toddler fed both Penny and herself little bites of waffle by hand.

Sheldon sat across from them mumbling, "So unsanitary. Is it really that hard to use a fork?"

Penny ignored him, focusing on the sweet smelling, warm, soft, bundle of joy in her arms. She wished the moment could last forever.

* * *

A few hours later, Penny was at the park swinging with Lizzie in her lap. The toddler was squealing, "Higher! Higher, mom-um, Penny!"

Sheldon watched from a safe distance with a frown on his face. He had wanted Lizzie to wear a helmet, but Penny thought that was ridiculous.

Other than a few whiny Sheldon moments, Penny was having a great day. Leonard had met Carole for breakfast and a day of shopping. Howard and Raj were doing there own things today, so when Sheldon had suggested they go out and buy Lizzie some clothes, Penny had happily agreed.

They went to the mall bought a couple outfits and a few toys for the toddler, had lunch, then decided to go to the park and play.

"Down!" Lizzie suddenly yelled.

Penny stopped and gently set Lizzie on her feet.

The toddler took off toward a sandbox were a couple of other kids were playing and joined them.

Penny walked over to a bench right next to it and sat down. Sheldon followed.

"Lizzie, whatever you do, don't put anything in your mouth," he commanded, and proceeded to lecture Penny on how unsanitary sand boxes were.

Penny swore she saw Lizzie actually roll her eyes.

She ignored Sheldon and watched in fascination as Lizzie seemed to take charge of the other two kids. They looked to be at least a year older than her, but quickly obeyed her directions and started building a sand castle.

It was almost as if Lizzie was the perfect combination of herself and Sheldon, in both appearance and personality… Weird. She wondered if the strangers who had crossed their paths today assumed that they were a family.

It took a minute before Penny realized that Sheldon had stopped talking.

He sat beside her on the bench, his face thoughtful as he glanced back and forth between her and Lizzie.

"What is it?" She asked, when he looked at her again.

He shrugged.

"I've never thought of you in the context of being a mother anymore than I have thought of myself in the context of being a father. Though, the other parents in this park have probably come to that conclusion with no hesitation. It's…fascinating."

Penny laughed.

"You know what's weird? I was kinda thinking the same thing."

They shared a grin, then Penny sighed, unhappily.

"I have the evening shift tonight."

"I can watch Lizzie," he said, wondering at her sadness.

"I know, I just… I don't want leave her. Is that strange? All day I've been trying so hard not to think further ahead than the next minute, but each minute seems to go by faster than the last. Before I know it, she'll be gone…" Penny swallowed and her eyes stung with tears.

Out of the corner of her eye, she saw Sheldon reach out to touch her shoulder, and then withdraw his hand. He tried again, but still couldn't bring himself to touch her.

Penny gave a quiet laugh and shook her head. The idea that she and Sheldon would ever have a child together was laughable. He couldn't even bring himself to touch her, let alone do anything else that led to baby-making.

But then he did it. She stilled as she felt the warm weight of his hand press down on her shoulder. Slowly she turned her head to look at him. He was staring at his hand as if he couldn't believe it was touching her either.

He suddenly jerked it away. "Sorry," he muttered, crossing his arms in front of his chest.

Penny shook her head.

"We're friends, Sheldon. You don't have to apologize for comforting a friend," she said, patting his shoulder softly.

He nodded, but didn't look at her.

Penny sighed again and looked at her watch.

Time to head home if she was going to make it to work.

She got to her feet.

"Lizzie! It's time to go," she called.

As the toddler ran toward her, Penny found herself suddenly hoping that they wouldn't find the girl's family. Maybe Penny could adopt her, and truly be her mother. As soon as she thought it, she knew it could never happen. First off, a precious little girl like that was bound to have a family worried sick about her. And if for some reason she didn't, no way would anyone allow a single, waitress who could barely pay her rent and utilities have custody of a toddler.

Penny's heart was heavy as they went back to the apartment.

End Chapter Two


	4. Chapter 4

Title: The Progeny Refutation of the Chronology Protection Conjecture 4/5

Author: Alyce Gates

Rating K

Summary: A Big Bang Theory Time Travel Fic (Penny/Sheldon)

Special Thanks to Syrus, my awesome beta.

Chapter Three

Sheldon and Lizzie were sitting on the sofa watching roadrunner cartoons when Leonard got home that evening.

"Hi Sheldon, hello Lizzie?" he said her name like it was a question as he shut the door behind him and dropped his key in the bowl.

The toddler looked at him, waved sleepily, and turned back to the television.

"Hello Leonard," Sheldon said with a sigh.

"Sheldon, what is Lizzie doing here?" He asked, trying to keep his tone light so as not to alarm the little girl.

"She's watching cartoons, Leonard. I thought that would be obvious," Sheldon commented.

"No, I mean, I thought the police were going to pick her up today. Have they located her family? And where is Penny?"

Sheldon sighed again and muted the television.

Lizzie made no protests as she was slowly falling asleep.

"I called the police this morning and told them that we had found her family, and the whole thing was a misunderstanding. They could look for her family, but would never find them. And Penny is at work right now."

Leonard crossed his arms across his chest, tilted his head and squinted at Sheldon.

"So, you found her family?" He asked, uncertainly.

"Yes, I believe so," Sheldon responded, quietly.

"Ok, then where are they?"

Sheldon slowly rose from the sofa and started pacing behind it.

"We played Lord of the Rings Monopoly, and she beat me. She's extremely intelligent for a three year old Leonard," he said, eyes flicking toward the now sleeping toddler.

Leonard arched and eyebrow.

"So?"

"So, I think…, no, I know that Lizzie is my daughter," Sheldon declared. The expression on his face was half proud half terrified.

"What!"

"Shh… You'll wake her. She had a busy day and needs a nap."

"Sheldon, that's ridiculous. Lizzie is not your daughter," Leonard said, keeping his voice quieter.

Sheldon gave Leonard a look that said he pitied the limitations of the other man's mind.

"Yes, she is, or she will be anyway."

Leonard scoffed and dropped into a chair.

"Okay, let's hear it," he said with a sigh.

"She has my IQ, my eyes, and my birthmark," Sheldon said, pulling his shirt over his head and turning away from Leonard so that his birthmark would be visible.

Leonard stared at it for a minute.

"I didn't know you had that… Okay, it's an odd coincidence…"

"Mee-Maw, Mother, Missy, & I all have one. Same shape, same place."

Leonard was quiet for a while as he pondered this.

"So, if she's your daughter, then would have had to have sex with someone almost four years ago," he pointed out and Sheldon cringed.

"Unless… Did you go back to that sperm bank?"

Sheldon shook his head quickly.

"Neither conjecture is correct. Lizzie is my daughter. She just hasn't been born yet. It's the only solution that makes any sense, really."

"What?"

"Time Travel, Leonard. Aren't you paying attention?" Sheldon asked.

Leonard just shook his head.

"There must have been some sort of accident or mistake. Lizzie was either transported here, or taken here by someone else and left. So, either someone will come looking for her, most likely my future self, or she is stuck here and I am unable to get her back. Either way, handing her over to the police will not be helpful."

"Sheldon, this is crazy, even for you," Leonard said sternly.

Sheldon shot him an offended look.

"No, Sheldon, you call the police and get this straightened out. I'm meeting Carole at the movies soon. If you haven't called them by the time I get back, I will," he threatened.

Sheldon gave him a long calculating look.

"Okay Leonard, I'll get it straightened out," he agreed calmly.

Too calmly.

Leonard gave him a suspicious look, and then went to shower and change.

* * *

One minute and forty-six seconds after Leonard left (the exact amount of time it took Leonard to walk down the stairs and out to the parking lot) there was a series of knocks on the door.

*Knock, Knock, Knock*

"Sheldon?"

*Knock, Knock, Knock*

"Sheldon?"

*Knock, Knock, Knock*

"Sheldon?"

The voice was familiar, yet strange. Sheldon had never heard it coming from the other side of a door before.

He walked over to the door, took a deep breath, and opened it.

"I thought it would be you," he told the man.

The man nodded, and was about to come inside, but Sheldon held out a hand.

"Not so fast. How do I know it's really me?" He asked.

The other, older Sheldon rolled his eyes.

"Our Mee-Maw calls us 'Moonpie' cause we're so nummy she could eat us right up," he said, flatly.

"Okay, come in," Sheldon said, stepping back.

"Thank you," Future Sheldon said.

His eyes fell on the toddler sleeping on the sofa and his whole body seemed to relax.

"It's strange, I knew she would be safe here, but still…" he trailed off and walked over to the sofa.

"What happened? How did she get here?" Sheldon asked, curiously.

Future Sheldon narrowed his eyes. "I can't tell you much. Just what I remember my older self telling me all those years ago."

"What did he tell you?"

"No, you have to ask," Future Sheldon responded with a smirk.

Sheldon sighed.

"Fine. Lizzie really is my daughter?"

A nod.

"And, her mother?" Sheldon asked, mouth going dry.

"Yes, it's her. Don't ask how, it's a long story. But it does happen, and here's the proof," Future Sheldon gently picked up the sleeping toddler and cuddled her close.

"There's Daddy's little princess," he cooed, and Lizzie smiled in her sleep.

He looked up at Sheldon with a grimace.

"I have to get her home. P-um, her mother is literally sick with worry," he explained quickly.

Sheldon nodded absently. His heart was racing and his head was spinning over all of the revelations that had been assaulting him since the night before.

Future Sheldon headed for the door and Sheldon opened it for him.

He paused before stepping across the threshold.

"Two more things. One- Lizzie is not a test tube baby. Two- She is not our only child."

For the first time, Sheldon was treated to his own superior smirk. And then, Lizzie and Future Sheldon were gone.

Sheldon went to his desk to down load the pictures he had taken of the white boards this morning before he'd wiped them clean. He would never forget the night he met Lizzie, for it was the night that he discovered how time travel could work.

End Chapter Three

Only the epilogue left. Will try to post it later tonight!

-Alyce


	5. Chapter 5

Title: The Progeny Refutation of the Chronology Protection Conjecture 5/5

Author: Alyce Gates

Rating K

Summary: A Big Bang Theory Time Travel Fic (Penny/Sheldon)

Special Thanks to Syrus, my awesome beta.

Epilogue:

Penny knocked then pushed the apartment door open.

"Sheldon? Lizzie?" She called, setting her purse down in a chair.

She had such a burning desire to see Lizzie she had left work almost an hour early.

Sheldon emerged from his bedroom and walked out into the living room to greet her.

"Hello Penny, how was work?" He asked, politely, though they both knew he could care less.

"Uh, fine. Where's Lizzie?"

Sheldon sat in his spot, and gestured for Penny to sit next to him. She complied.

"Lizzie's gone."

Penny jumped to her feet again.

"Gone? What do you mean, gone? Sheldon, what did you do?" She demanded.

Sheldon looked insulted.

"I didn't do anything. Her father came for her. I'm sorry you didn't get to say goodbye, but he was in a hurry. Her mother was very worried," he explained.

All the fight left Penny and she slumped down onto the sofa in a heap.

"Oh, well I … I mean, that's great. I'm glad they found her," she said, voice breaking a little.

Penny stared down at her hands. They were clenched into fists so tight, her fingers were turning white.

Sheldon's stomach hurt. He knew Penny was terribly upset. Any minute now the dam would break and she would be sobbing. She would probably get tears and mucous all over the sofa.

If Leonard were there, he would give Penny a hug. Sheldon thought about the two times he had hugged Penny. The first had been worth it. He still had Leonard Nimoy's DNA under lock and key until he could find what he needed to experiment with it.

The second time he hugged her, he had gotten incredibly sick. It would be risky to try it again, but then his mind went to Lizzie. Not a test tube baby.

He gulped. Took a deep breath, let it out, then slowly put his arm around Penny. She stilled for a second. He slightly pulled her toward him, and she went willingly. Her face rested against his chest, her arm looped around his waist.

The tears came quickly in harsh sobs that shook her whole body. He had to fight the urge to push her away, especially when he felt her tears begin to soak through his shirt and onto his skin.

Sheldon made himself do it. He knew he could, he'd seen the proof. And when he was able to push the germaphobia away, he realized just how 'right' it all felt.

He smiled.

"There, there," Sheldon said, rubbing his hand in a soft circle on Penny's back.

"Sheldon's here."

The End

My idea for the next story is Sheldon coming to terms with the fact that he and Penny will engage in coitus. (Higher Rating) What do you guys thing? Should I do it?

-Alyce

Oh, and for the few people who asked about the title:

Progeny= Children (Sheldon & Penny's children specifically)

Refutation= To refute or disprove

Chronology Protection Conjecture = is a conjecture by the Stephen Hawking that the laws of physics are such as to prevent time travel


End file.
